Salimian Razieh, Shahrokhian Saeed, Panahi Saba
Department of Chemistry, Sharif University of Technology, Azadi Ave., Tehran 11155-9516, Iran.
Institute for Nanoscience and Technology, Sharif University of Technology, Azadi Ave., Tehran 11155-9516, Iran.
ACS Biomater Sci Eng. 2019 May 13;5(5):2587-2594. doi: 10.1021/acsbiomaterials.8b01520. Epub 2019 Apr 3.
Herein, we present a novel, simple, and ultrasensitive electrochemical DNA (E-DNA) sensor based on hollow carbon spheres (HCS) decorated with polyaniline (PANI). A thiolated 21-mer oligonucleotide, characteristic of HBV DNA, is immobilized via electrodeposited gold nanoparticles on HCS-PANI. Cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) are used to characterize the electrochemical properties of the prepared nanocomposite. Scanning electron microscopy is employed to investigate the morphological texture of the fabricated modifier. An enhanced intrinsic signal of PANI is probed to evaluate the biosensing ability of the prepared modifier. The proposed biosensor allows for the detection of the target sequences of HBV DNA at a concentration as low as 10 fM (i.e., 10 DNA copies/mL). In addition, this biosensor demonstrated good capability to differentiate between the perfectly matched target oligonucleotide and three nucleotide-mismatched oligonucleotides. Furthermore, the HCS/PANI-based E-DNA sensor indicates highly sensitive detection of HBV DNA in real samples.
在此，我们展示了一种基于用聚苯胺（PANI）修饰的空心碳球（HCS）的新型、简单且超灵敏的电化学DNA（E-DNA）传感器。一种具有乙肝病毒DNA特征的硫醇化21聚体寡核苷酸通过电沉积金纳米颗粒固定在HCS-PANI上。循环伏安法（CV）、差分脉冲伏安法（DPV）和电化学阻抗谱（EIS）用于表征所制备的纳米复合材料的电化学性质。扫描电子显微镜用于研究所制备修饰剂的形态结构。探测聚苯胺增强的固有信号以评估所制备修饰剂的生物传感能力。所提出的生物传感器能够检测低至10 fM（即10个DNA拷贝/毫升）浓度的乙肝病毒DNA靶序列。此外，该生物传感器在区分完全匹配的靶寡核苷酸和三种核苷酸错配的寡核苷酸方面表现出良好的能力。此外，基于HCS/PANI的E-DNA传感器在实际样品中对乙肝病毒DNA显示出高灵敏检测。
